#! /bin/sh
# Split link-edit into two stage for linking static applications with
# Xenomai user-space posix skin.

set -e

usage() {
    cat <<EOF
$1 [options] command-line

Split command-line in two parts for linking static applications with
Xenomai user-space posix skin in two stages.

Options:
-q be quiet
-v be verbose (print each command before running it)

Example:
$1 -v gcc -o foo foo.o -Wl,@/usr/xenomai/lib/posix.wrappers -L/usr/xenomai/lib -lpthread_rt -lpthread -lrt
will print and run:
+ gcc -o foo.tmp -Wl,-Ur -nostdlib foo.o -Wl,@/usr/xenomai/lib/posix.wrappers -L/usr/xenomai/lib
+ gcc -o foo foo.tmp -L/usr/xenomai/lib -lpthread_rt -lpthread -lrt
+ rm foo.tmp
EOF
}

add_2stages() {
    stage1_args="$stage1_args $@"
    stage2_args="$stage2_args $@"
}   

add_linker_flag() {
    if $next_is_wrapped_symbol; then
	stage1_args="$stage1_args -Wl,--wrap $@"
	next_is_wrapped_symbol=false
    else
	add_2stages "$@"
    fi
}

add_linker_obj() {
    if $stage2; then
	stage2_args="$stage2_args $@"
    else
	stage1_args="$stage1_args $@"
    fi
}

if test -n "$V" && test $V -gt 0; then
    verbose=:
else
    verbose=false
fi
progname="$0"

if test $# -eq 0; then
    usage "$progname"
    exit 0
fi

while test $# -gt 0; do
    arg="$1"
    shift
    case "$arg" in
	-v) 
	    verbose=:
	    ;;

	-q) 
	    verbose=false
	    ;;

	-*)
	    cc="$cc $arg"
	    ;;

	*gcc*|*g++*)
	    cc="$cc $arg"
	    break
	    ;;

	*ld)
	    usage "$progname"
	    /bin/echo -e "\nlinker must be gcc or g++, not ld"
	    exit 1
	    ;;

	*)
	    cc="$cc $arg"
	    ;;
    esac
done

next_is_wrapped_symbol=false

onestage_args="$@"
stage1_args=""
stage2_args=""
stage2=false
while test $# -gt 0; do
    arg="$1"
    shift
    case "$arg" in
	*pthread_rt*)
	    stage2_args="$stage2_args $arg"
	    stage2=:
	    ;;

	-Xlinker)
	    arg="$1"
	    shift
	    case "$arg" in
		--wrap)
		    next_is_wrapped_symbol=:
		    ;;
		@*posix.wrappers)
		    stage1_args="$stage1_args -Xlinker $arg"
		    ;;

		*) 
		    add_linker_flag -Xlinker "$arg"
		    ;;
	    esac
	    ;;

	-Wl,--wrap)
	    next_is_wrapped_symbol=:
	    ;;

	-Wl,@*posix.wrappers|-Wl,--wrap,*)
	    stage1_args="$stage1_args $arg"
	    ;;

	-Wl,*)
	    add_linker_flag "$arg"
	    ;;

	-o)
	    output="$1"
	    shift
	    ;;

	-o*)
	    output=`expr "$arg" : '-o\(.*\)'`
	    ;;
	
	-l) 
	    arg="$1"
	    shift
	    add_linker_obj -l $arg
	    ;;

	-l*) #a library
	    add_linker_obj $arg
	    ;;

	*.so)
	    stage2_args="$stage2_args $arg"
	    ;;

	*) 
	    if test -e "$arg"; then
		add_linker_obj $arg
	    else
		add_2stages "$arg"
	    fi
	   ;;
    esac
done

if $stage2; then
    $verbose && set -x
    $cc -o "$output.tmp" -Wl,-Ur -nostdlib $stage1_args
    $cc -o "$output" "$output.tmp" $stage2_args
    rm -f $output.tmp
else
    $verbose && set -x
    $cc -o "$output" $onestage_args
fi
